A photovoltaic string includes several photovoltaic modules connected in series, and is configured to absorb solar energy and convert the solar energy to electric energy, to become effective input of an inverter. Because the photovoltaic string is installed in an outdoor environment for a long time, and is affected by a high temperature, high humidity, a hot spot, mechanical damage, and the like, and may also be affected by shadow, accumulated dust and snow, and the like. As a result, the modules convert solar energy to electric energy less efficiently, and some modules fail and therefore become abnormal. To ensure normal working of the photovoltaic string, in an actual application, the modules are monitored in real time by a monitoring center. In a monitoring process, data of each module is sampled in real time, the sampled data of the module is obtained in a wireless or wired communication manner for abnormality analysis, and once it is determined that a module is abnormal, the module is located for eliminating abnormality.
To accurately locate an abnormal module, when a photovoltaic power generating system is established and commissioned, each module is equipped with a module voltage monitoring apparatus, and the monitoring center is connected to the module voltage monitoring apparatus in a wireless or wired communications manner, where communication addresses of all module voltage monitoring apparatuses are different. A location of a module is numbered according to a location sequence of the module in the photovoltaic string, a one-to-one correspondence is established between a location number and a communication address used by a module voltage monitoring apparatus corresponding to the module, and the correspondence is recorded into a monitoring device. When it is determined that a module is abnormal, a communication address of a module voltage monitoring apparatus corresponding to the module is first obtained, and a location number of the abnormal module is found according to the correspondence, to determine a location of the abnormal module in the photovoltaic string. It can be seen that, the correspondence between a location number of a module and a communication address is recorded in a manual manner. However, when there is a relatively large total quantity of photovoltaic panels, manual recording may cause a very heavy workload, and increase complexity of installation and commissioning at an early stage. Consequently, it is difficult to implement installation and commissioning.